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| author | Salvatore Mesoraca <s.mesoraca16@gmail.com> | 2018-07-16 21:10:34 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-07-18 15:08:31 -0700 |
| commit | 0015b80abccecca82622d9e9d48eb210572a0c3b (patch) | |
| tree | 9e3baafb4384706952f74369f318bee0827b3abe /net/dsa | |
| parent | 14260e91707a7844206aeac10daa462cd3b1538d (diff) | |
| download | linux-stable-0015b80abccecca82622d9e9d48eb210572a0c3b.tar.gz linux-stable-0015b80abccecca82622d9e9d48eb210572a0c3b.tar.bz2 linux-stable-0015b80abccecca82622d9e9d48eb210572a0c3b.zip | |
net: dsa: Remove VLA usage
We avoid 2 VLAs by using a pre-allocated field in dsa_switch. We also
try to avoid dynamic allocation whenever possible (when using fewer than
bits-per-long ports, which is the common case).
Link: http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Link: http://lkml.kernel.org/r/20180505185145.GB32630@lunn.ch
Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
[kees: tweak commit subject and message slightly]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dsa')
| -rw-r--r-- | net/dsa/dsa2.c | 14 | ||||
| -rw-r--r-- | net/dsa/switch.c | 22 |
2 files changed, 24 insertions, 12 deletions
diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c index dc5d9af3dc80..a1917025e155 100644 --- a/net/dsa/dsa2.c +++ b/net/dsa/dsa2.c @@ -775,6 +775,20 @@ struct dsa_switch *dsa_switch_alloc(struct device *dev, size_t n) if (!ds) return NULL; + /* We avoid allocating memory outside dsa_switch + * if it is not needed. + */ + if (n <= sizeof(ds->_bitmap) * 8) { + ds->bitmap = &ds->_bitmap; + } else { + ds->bitmap = devm_kcalloc(dev, + BITS_TO_LONGS(n), + sizeof(unsigned long), + GFP_KERNEL); + if (unlikely(!ds->bitmap)) + return NULL; + } + ds->dev = dev; ds->num_ports = n; diff --git a/net/dsa/switch.c b/net/dsa/switch.c index b93511726069..142b294d3446 100644 --- a/net/dsa/switch.c +++ b/net/dsa/switch.c @@ -136,21 +136,20 @@ static int dsa_switch_mdb_add(struct dsa_switch *ds, { const struct switchdev_obj_port_mdb *mdb = info->mdb; struct switchdev_trans *trans = info->trans; - DECLARE_BITMAP(group, ds->num_ports); int port; /* Build a mask of Multicast group members */ - bitmap_zero(group, ds->num_ports); + bitmap_zero(ds->bitmap, ds->num_ports); if (ds->index == info->sw_index) - set_bit(info->port, group); + set_bit(info->port, ds->bitmap); for (port = 0; port < ds->num_ports; port++) if (dsa_is_dsa_port(ds, port)) - set_bit(port, group); + set_bit(port, ds->bitmap); if (switchdev_trans_ph_prepare(trans)) - return dsa_switch_mdb_prepare_bitmap(ds, mdb, group); + return dsa_switch_mdb_prepare_bitmap(ds, mdb, ds->bitmap); - dsa_switch_mdb_add_bitmap(ds, mdb, group); + dsa_switch_mdb_add_bitmap(ds, mdb, ds->bitmap); return 0; } @@ -204,21 +203,20 @@ static int dsa_switch_vlan_add(struct dsa_switch *ds, { const struct switchdev_obj_port_vlan *vlan = info->vlan; struct switchdev_trans *trans = info->trans; - DECLARE_BITMAP(members, ds->num_ports); int port; /* Build a mask of VLAN members */ - bitmap_zero(members, ds->num_ports); + bitmap_zero(ds->bitmap, ds->num_ports); if (ds->index == info->sw_index) - set_bit(info->port, members); + set_bit(info->port, ds->bitmap); for (port = 0; port < ds->num_ports; port++) if (dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)) - set_bit(port, members); + set_bit(port, ds->bitmap); if (switchdev_trans_ph_prepare(trans)) - return dsa_switch_vlan_prepare_bitmap(ds, vlan, members); + return dsa_switch_vlan_prepare_bitmap(ds, vlan, ds->bitmap); - dsa_switch_vlan_add_bitmap(ds, vlan, members); + dsa_switch_vlan_add_bitmap(ds, vlan, ds->bitmap); return 0; } |